Why are my plant's leaves turning yellow?
Why Are My Plantâs Leaves Turning Yellow?
Yellowing leaves (chlorosis) are one of the most common plant problems, and they can have several different causes. The key to fixing the issue is identifying the underlying problem. Hereâs how to diagnose and treat yellowing leaves:
Common Causes of Yellow Leaves
1. Overwatering (Most Common)
Symptoms:
- Yellowing starts with lower, older leaves
- Leaves are soft and mushy
- Soil is constantly wet
- May see fungus gnats or smell musty odor
- Stems may appear soft or dark
Solution:
- Allow soil to dry out before watering again
- Check that pot has drainage holes
- Remove affected leaves
- Consider repotting if root rot has set in
- Reduce watering frequency going forward
Prevention:
- Use the finger test before watering (check if top 2 inches are dry)
- Ensure pots have proper drainage
- Use well-draining soil
2. Underwatering
Symptoms:
- Yellowing often accompanied by browning, crispy edges
- Soil is bone dry and may pull away from pot edges
- Leaves are dry and papery
- Plant appears droopy or wilted
- Pot feels very light
Solution:
- Water thoroughly until water drains from bottom
- Increase watering frequency
- Consider whether plant needs repotting
Prevention:
- Check plants regularly
- Water deeply when soil is dry
- Donât let soil become completely desiccated
3. Nutrient Deficiency
Symptoms:
- Older leaves turn yellow while veins remain green
- New growth may be pale or yellowish
- Overall slow or stunted growth
- Has been in same soil for 1+ years
Solution:
- Feed with balanced liquid fertilizer
- For nitrogen deficiency: yellowing of older leaves
- For iron deficiency: yellowing between veins on new growth
- Consider repotting with fresh soil
Prevention:
- Fertilize during growing season (spring/summer)
- Use balanced fertilizer every 4-6 weeks
- Repot every 1-2 years to refresh soil
4. Too Much Light
Symptoms:
- Leaves turn pale yellow or almost white
- May see brown, crispy patches (sunburn)
- Primarily affects leaves closest to light source
- Happened after moving to brighter location
Solution:
- Move plant away from direct sunlight
- Add sheer curtain to filter light
- Gradually acclimate plants to brighter conditions
Prevention:
- Know your plantâs light requirements
- Transition plants to new light conditions gradually
- Provide bright indirect light for most tropicals
5. Too Little Light
Symptoms:
- Lower leaves turn yellow and drop off
- Plant appears âleggyâ or stretched
- New growth is smaller and pale
- Little to no new growth
Solution:
- Move plant to brighter location
- Rotate plant regularly for even light exposure
- Consider grow lights for low-light areas
Prevention:
- Choose plants appropriate for your light conditions
- Provide at least some natural light
- Use supplemental grow lights in dim spaces
6. Natural Aging
Symptoms:
- Only the oldest, lowest leaves turn yellow
- Plant otherwise appears healthy
- New growth is green and vigorous
- Happens gradually over time
Solution:
- This is normal! Simply remove yellow leaves
- Continue regular care routine
No prevention needed:
- All plants naturally shed old leaves as part of their life cycle
7. Temperature Stress or Drafts
Symptoms:
- Sudden yellowing after temperature change
- Leaves near windows, AC vents, or heaters affected
- May occur seasonally
Solution:
- Move plant away from cold drafts or heat sources
- Avoid placing near air conditioning or heating vents
- Keep temperature consistent (65-75°F for most tropicals)
Prevention:
- Place plants away from drafty windows and doors
- Avoid extreme temperature fluctuations
- Move plants from cold windows in winter
8. Pest Infestation
Symptoms:
- Yellowing accompanied by sticky residue, webbing, or visible insects
- May see tiny dots or stippling on leaves
- Affects multiple leaves relatively quickly
Solution:
- Identify the pest (spider mites, aphids, scale, etc.)
- Treat with insecticidal soap, neem oil, or appropriate pest control
- Isolate affected plant from others
- See our pest guides for specific treatment
Prevention:
- Inspect plants regularly
- Quarantine new plants
- Keep leaves clean and dust-free
- Maintain good air circulation
Diagnosis Flowchart
Ask yourself these questions:
- Is the soil wet? â Likely overwatering
- Is the soil bone dry? â Likely underwatering
- Only bottom, old leaves? â Could be natural aging or nutrient deficiency
- Do you see pests or webbing? â Pest problem
- Near a window/vent? â Temperature or light stress
- Recent location change? â Adjustment period or light change
- In same soil for over a year? â Nutrient depletion
Quick Reference Guide
| Pattern | Likely Cause |
|---|---|
| Lower leaves, wet soil | Overwatering |
| Lower leaves, dry soil | Underwatering |
| Leaves closest to window | Too much light/sunburn |
| Lower leaves, leggy growth | Too little light |
| One or two oldest leaves | Natural aging |
| Sudden, multiple leaves | Pest, disease, or stress |
| Yellow between veins | Nutrient deficiency |
What to Do Next
- Assess the whole plant: Look for additional symptoms
- Check soil moisture: Use the finger test
- Inspect for pests: Look under leaves and along stems
- Review recent changes: New location, watering changes, etc.
- Take action: Address the most likely cause
- Remove yellow leaves: They wonât turn green again
- Be patient: Plants take time to recover
Prevention Tips
- Establish a routine: Check plants weekly
- Water wisely: Use the finger test, not a schedule
- Provide proper light: Match plant to location
- Fertilize appropriately: Feed during growing season
- Inspect regularly: Catch problems early
- Keep notes: Track what works for each plant
When to Worry
A few yellow leaves here and there are normal, but seek help or investigate further if:
- More than 25% of leaves are yellow
- Yellowing is rapid and spreading
- Accompanied by other severe symptoms (rot, severe wilting, pest infestation)
- Plant doesnât improve after adjusting care
Bottom Line
Yellowing leaves are usually a sign that something in your plantâs care needs adjustment. By systematically working through the common causes, you can identify the issue and take corrective action. Remember, patience is keyâplants need time to recover and produce new, healthy growth.
Most importantly, learn from the experience. Understanding why leaves turned yellow will help you provide better care going forward!